<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>rem布局准备</title>
    <style>
        *{
            margin: 0;
            padding: 0;
        }
        html{
            font-size: 100px;
        }
        body{
            font-size: 16px;
        }
        .box{
            width: 750rem;
            height: 100px;
            background: yellow;
        }
    </style>
    <script>
        document.documentElement.style.fontSize = document.documentElement.clientWidth / 750 * 1 + "px";
    </script>
</head>
<body>
    <div class="box">
        赵谦孙俪
    </div>
</body>
</html>